Hydraulic bearing



Dec. l0, 1963 G. R.`cARRoLL 3,113,8}08

HYDRAULIC BEARING Filed May 15' 1962 o 1 GEORGE R. CARROLL AT TORNEY- United States Patent Olice lllld Patented Dec.. 10, 1963 3,113,808 HYDRAULIC BEARlNG George R. Carroll, Columbus, hio, assigner to North American Aviation, lne. Filed May l5, i962, Ser. No. 194,771 4 Claims. (Cl. 308--9) This invention concerns a hydraulic bearing and particularly relates .to a hydraulic bearing having a hydraulic system with improved hydraulic duid now-control means provided therein.

An important object of this invention is to provide a hydraulic bearing which develops a constant hydraulic fluid hlm thickness as between runner surface and slll `surface components of the bearing throughout changing operating conditions.

Another object of this invention is `to provide a hydraulic bearing which develops `a hydraulic iluid ilow between runner surface and sill surface components of the bearing that is not adected by hydraulic system input or output pressure fluctuations.

Another object of this invention is to provide a hydraulic bearing with a hydraulic system iluid flow-control or metering ineans that develops compensation for 'hydraullic iiuid viscosity changes c-aused by temperature variations to maintain a constant hydraulic fluid film thickness as between runner surface and sill surface components of a hydraulic bearing.

A still further object of this invention is 4to provide a hydraulic bearing which develops a constant hydraulic fluid film thickness as between runner surface and sill surface components oi a hydraulic bearing during changing operating conditions and which has a minimum sensitivity to contamination.

Other objects 'and advantages of this invention will become apparent during consideration of the description and drawings.

ln the drawings:

FIG. 1 is `a perspective view of a bearing which incorporates the features of this invention;

FlG. 2 is a schematic illustration of the hydraulic system incorporated in the hydraulic bearing of FlG. l;

FlG. 3 is a sectional view of the improved hydraulic fluid control or metering means incorporated in the hydraulic bearing of FIG. 1 and in the hydraulic system of FIG. 2; and

PEG. 4 is a perspective view of a portion of another embodiment of the bearing of this invention.

The hydraulic bearing of this invention is designated generally by the refe-rence numeral lll of Fl'G. l. Bearing lll supports the base member shown as ll. ln one application of this invention, base member ll is part ot the azimuth support or a large-diameter antenna having a gross weight in excess of 375,600 pounds. In that application, hydraulic bearing l@ is provided to develop precision support for the antenna structure as that structure is rotated yin azimuth for tracking purposes. Hydraulic bearing develops a resistance to rotation which is nil or negligible, maintains -a constant hydraulic uid iiim tln'ckness as between the hearing and base member lll, and provides both 'thrust and radial position control.

Hydraulic bearing lll includes a block l2 containing pool recesses 13 and ld. Pool recesses i3 are provided in the upper sill surface l5 of block l2 to develop thrust support for base member lll. Pool recesses ld are provided in the vertical sill surface le of block l2 to develop radial position control `for base member ll. Undersurface portions i7 `and 11S of base member il cooperate with sill `surfaces l5 and 16, respectively. However, surfaces 17 and i8 are separated from surfaces l5 yand le by ya ilm of hydraulic iiuid having a constant thickness throughout changing operating conditions of loading pressures, viscosity, and temperature. ln this description, surfaces 17 and 18 'are referred to as runner surfaces.

During operation of the bearing system invention described herein, hydraulic bearing itl and base member il are maintained in their respective operating positions by the hydraulic system disclosed schematically in FIG. 2. ln that system, hydraulic iluid i9 is supplied to pool recesses i3 and ldthrough the pump means 2li and through the manifold means 2l. Hydraulic line portions 22 and 2,3 supply hydraulic fluid i9 from the i'luid reservoir 24. to pump means Ztl and from pump means Ztl to manifold 2li, respectively. Each pool recess l5 or ld in hydraulic bearing l@ is supplied with pressurized hydraulic duid through the improved how-control valve 25 of this invention. Each flow-control valve 25 is operatively connected to manifold 2l lby hydraulic line portion 26 and to lan interior passageway 27 in block l2 by a hydraulic line portion such las 23. Each passageway' 27 conducts iluid from a hydraulic line portion 213 to a pool recess i3 or to a pool recess ld. Hydraulic iluid flowing from between ,the block portion l2 of hydraulic bearing lll and base member ll is received in the sump designated 29 and returned to reservoir 2d through the fluid line designated 30.

Details of the improved hydraulic iiuid flow-control or metering means 25 incorporated in this invention are provided in FIG. 3. 'Ihe housing of how-control means Z5 includes la body portion 3l and end plates 32 and 33. End plate 33 dinners from end plate 32 essentially in that it contains an adjustment means for varying the performance characteristic olf the flow-control means. End plates 32, and 33 are secured lto body Ell by the fasteners designated 34. The seal means designated 35 are provided for eliminating leak-age as between the body and end plate portions of unit 25. `Flow-control means 25 also includes the porting sleeve designated 35. VJithin the cylindrical interior chamber 37 defined by porting sleeve 3o is located a valve member referenced generally as 3S. Valve member 3S includes stem portions 39 and itl and spool portions el and 42. Spool portion l2 provides a throttling function and, in part at least, regulates the iiow of hydraulic fluid through unit 2S. Spool portion 4l is provided to maintain a constant pressure dilterential in the valve as hereinafter detailed. Porting sleeve Se includes annular passageway and port combinations 43, 44, and 4S. Interior intersecting passageways 56 and 47 are provided ln valve member 3S in la manner whereby hydraulic lluid pressure is maintained at the same pressure level 4at either side of spool portion d2.

Hydraulic line portions 26 and 28 `are operatively connected to `dow-control means 25 by the ittings designated lll and 4'?. Pressurized `fluid received yfrom` pump means 20 passes into `annular passageway 45 and yis ported into that portion ot interior chamber 37 located intermediate spool portions il tand d2. Such iluid is also ported at the same pressure into the end portion of interior chambe-r 3'7 located adjacent spool i2 through the passage- Ways `designated le and 47. Pressurized uid received in the chamber portion intermediate spools di and 4Z is further ported to and from fixed-value capillary means 5th through the annular passageway-port combinations 44 and 43, respectively. Fixed-value capillary means 5d is connected to dow-control unit 25 by the conventional iittings designated 5l and 52,. The pressurized iluid is `afterward conducted from capillary means Sil into that portion of interior chamber 37 which is located to the lett (FlG. 3) of spool 4l and thereafter into hydraulic line portion 28 supplying a pool recess in bearing lll. Capillary means 56' is subjected to a constant pressure difterential by reason of the operation of balancing spool d1 Vand the Xed resistance value of the capillary tube portion.

atrasos Flow-control means Z also incorporates a compression spring 53. Spring 53 surrounds stem portion 3?, abuts spool portion 4l, `and :also abuts the adjustment piston designated 54. Piston 54 is spaced-apart from the end of stem 39 to permit longitudinal movement of valve mem.- ber 3S within its operating limits. Spring S3 is selected to provide a constant spring-loading lthroughout srnall displacements of valve 3:3. Such is especially true as to displacements of the left end (rFlG. 3) of spool 42 across the port portions of combination A slotted adjust rnent screw 5S and la locknut 55 are provided to facA .te adjustment or" the position of piston Seal moans 57 is provided to prevent leakage or pressurized hydraulic fluid from Within chamber `37 to the atmosphere through the threaded opening in end plate 33.

As s rown in iFlG. 4 of the drawings, it may be preierred that pool recesses 13 and la he provided in in dividual pad members 58 and 59 of given length and width which are separately `attached to block 12 by fasteners `#59. ln this manner the bearing will be provided with separated sill surface portions that are each well-defined as to extent of surface area.

The hydraulic bearing land hydraulic system of this invention operate to maintain a constant ilm thickness as between the runner surfaces 17 and 13 of base member 1i and the sill surfaces 15 and lo of bea-ring block 12 as pressurized fluid is circulated into and from pool recesses 13 and 14. The constant film thickness is main-tained even though changes occur to the operating conditions of the hydraulic bearing and hydraulic fluid systei.. Such changes include variations in inlet pressure established by pump means 2n, variations in outlet presure changed by the loading of base member lll, `and variations in hydraulic fluid viscosity caused by temperature changes or the like. Such improved performance is obtained essentially through use of improved dow-control means having the throttling and balancing spool valve 33 of uniform maximum cross-sectional diameter and the Xedvalue capillary means designated Sd. Performance of the system is such :that flow-control means 25 is not readily subjected to malfunction because of Atypical `fluid system contamination.

I claim:

1. In a hydraulic bearing having sill and runner surfaces `separated by `a lm of pressurized hydraulic fluid of constant thickness, in combination: pump means delivering pressurized hydraulic huid, and flow-control means metering the iiow of pressurized hydraulic duid delivered lby said pump means to the hydraulic bearing, said flow-control means comprising a capillary means having a fixed-value iiow resistance, 'and pressure-responsive valve means regulating the flow of iluid from said pump means to said capiliary means, said valve means maintaining la constant pressure differential across said capillary means when pressure loadings of the bearing 1ere changed Yand when pressure loadings of said pump means are changed.

2. The invention dened by claim l, wherein said valve means includes a pressure-responsive balancing spool portion and a throttling spool portion spaced-apart from said balancing `spool portion a fixed distance, said spool portions having equal cross-sectional areas.

3. A hydraulic bearing hav-ing .a runner surface, a sill surface, pool means containing pressurized hydraulic fluid which separates said ruimer surface iroi said sill surface by a constant distance, pump means delivering pressurized hydraulic fluid, capillary means of fixed length compensating for viscosity changes in pressurized hydraulic fluid transmitted therethrough to said pool means, and valve means controlling the quantity of pressurized hydraulic fluid delivered by said pump means to said capillary means, said valve means developing a pressure drop of Xed-value across said capillary means during load changes to said runner surface and during load changes to said pump means.

4. The invention defined by claim 3, wherein said valve means includes `a throttling valve which is longitudinally displaced to control the quantity of pressurired hydraulic fluid delivered to said capillary means and inciudes ya balancing valve movably responsive to changes in `the pressure diferences between inlet hydraulic luid and outlet hydraulic rluid pressures for said capillary means, said throttling valve being connected in i'ixed spaced-apart relation to and having the same cross-sectional areas as said balancing valve.

References Cited in the tile of this patent UNTED STATE@ PATENTS 

1. IN A HYDRAULIC BEARING HAVING SILL AND RUNNER SURFACES SEPARATED BY A FILM OF PRESSURIZED HYDRAULIC FLUID OF CONSTANT THICKNESS, IN COMBINATION: PUMP MEANS DELIVERING PRESSURIZED HYDRAULIC FLUID, AND FLOW-CONTROL MEANS METERING THE FLOW OF PRESSURIZED HYDRAULIC FLUID DELIVERED BY SAID PUMP MEANS TO THE HYDRAULIC BEARING, SAID FLOW-CONTROL MEANS COMPRISING A CAPILLARY MEANS HAVING A FIXED-VALUE FLOW RESISTANCE, AND PRESSURE-RESPONSIVE VALVE MEANS REGULATING THE FLOW OF FLUID FROM SAID PUMP MEANS TO SAID CAPILLARY MEANS, SAID VALVE MEANS MAINTAINING A CONSTANT PRESSURE DIFFERENTIAL ACROSS SAID CAPILLARY MEANS WHEN PRESSURE LOADINGS OF THE BEARING ARE CHANGED AND WHEN PRESSURE LOADINGS OF SAID PUMP MEANS ARE CHANGED. 